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Diffstat (limited to 'fs/xfs/linux-2.6/xfs_aops.c')
-rw-r--r--fs/xfs/linux-2.6/xfs_aops.c1506
1 files changed, 0 insertions, 1506 deletions
diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
deleted file mode 100644
index 79ce38b..0000000
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ /dev/null
@@ -1,1506 +0,0 @@
-/*
- * Copyright (c) 2000-2005 Silicon Graphics, Inc.
- * All Rights Reserved.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it would be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- */
-#include "xfs.h"
-#include "xfs_bit.h"
-#include "xfs_log.h"
-#include "xfs_inum.h"
-#include "xfs_sb.h"
-#include "xfs_ag.h"
-#include "xfs_trans.h"
-#include "xfs_mount.h"
-#include "xfs_bmap_btree.h"
-#include "xfs_dinode.h"
-#include "xfs_inode.h"
-#include "xfs_alloc.h"
-#include "xfs_error.h"
-#include "xfs_rw.h"
-#include "xfs_iomap.h"
-#include "xfs_vnodeops.h"
-#include "xfs_trace.h"
-#include "xfs_bmap.h"
-#include <linux/gfp.h>
-#include <linux/mpage.h>
-#include <linux/pagevec.h>
-#include <linux/writeback.h>
-
-
-/*
- * Prime number of hash buckets since address is used as the key.
- */
-#define NVSYNC 37
-#define to_ioend_wq(v) (&xfs_ioend_wq[((unsigned long)v) % NVSYNC])
-static wait_queue_head_t xfs_ioend_wq[NVSYNC];
-
-void __init
-xfs_ioend_init(void)
-{
- int i;
-
- for (i = 0; i < NVSYNC; i++)
- init_waitqueue_head(&xfs_ioend_wq[i]);
-}
-
-void
-xfs_ioend_wait(
- xfs_inode_t *ip)
-{
- wait_queue_head_t *wq = to_ioend_wq(ip);
-
- wait_event(*wq, (atomic_read(&ip->i_iocount) == 0));
-}
-
-STATIC void
-xfs_ioend_wake(
- xfs_inode_t *ip)
-{
- if (atomic_dec_and_test(&ip->i_iocount))
- wake_up(to_ioend_wq(ip));
-}
-
-void
-xfs_count_page_state(
- struct page *page,
- int *delalloc,
- int *unwritten)
-{
- struct buffer_head *bh, *head;
-
- *delalloc = *unwritten = 0;
-
- bh = head = page_buffers(page);
- do {
- if (buffer_unwritten(bh))
- (*unwritten) = 1;
- else if (buffer_delay(bh))
- (*delalloc) = 1;
- } while ((bh = bh->b_this_page) != head);
-}
-
-STATIC struct block_device *
-xfs_find_bdev_for_inode(
- struct inode *inode)
-{
- struct xfs_inode *ip = XFS_I(inode);
- struct xfs_mount *mp = ip->i_mount;
-
- if (XFS_IS_REALTIME_INODE(ip))
- return mp->m_rtdev_targp->bt_bdev;
- else
- return mp->m_ddev_targp->bt_bdev;
-}
-
-/*
- * We're now finished for good with this ioend structure.
- * Update the page state via the associated buffer_heads,
- * release holds on the inode and bio, and finally free
- * up memory. Do not use the ioend after this.
- */
-STATIC void
-xfs_destroy_ioend(
- xfs_ioend_t *ioend)
-{
- struct buffer_head *bh, *next;
- struct xfs_inode *ip = XFS_I(ioend->io_inode);
-
- for (bh = ioend->io_buffer_head; bh; bh = next) {
- next = bh->b_private;
- bh->b_end_io(bh, !ioend->io_error);
- }
-
- /*
- * Volume managers supporting multiple paths can send back ENODEV
- * when the final path disappears. In this case continuing to fill
- * the page cache with dirty data which cannot be written out is
- * evil, so prevent that.
- */
- if (unlikely(ioend->io_error == -ENODEV)) {
- xfs_do_force_shutdown(ip->i_mount, SHUTDOWN_DEVICE_REQ,
- __FILE__, __LINE__);
- }
-
- xfs_ioend_wake(ip);
- mempool_free(ioend, xfs_ioend_pool);
-}
-
-/*
- * If the end of the current ioend is beyond the current EOF,
- * return the new EOF value, otherwise zero.
- */
-STATIC xfs_fsize_t
-xfs_ioend_new_eof(
- xfs_ioend_t *ioend)
-{
- xfs_inode_t *ip = XFS_I(ioend->io_inode);
- xfs_fsize_t isize;
- xfs_fsize_t bsize;
-
- bsize = ioend->io_offset + ioend->io_size;
- isize = MAX(ip->i_size, ip->i_new_size);
- isize = MIN(isize, bsize);
- return isize > ip->i_d.di_size ? isize : 0;
-}
-
-/*
- * Update on-disk file size now that data has been written to disk. The
- * current in-memory file size is i_size. If a write is beyond eof i_new_size
- * will be the intended file size until i_size is updated. If this write does
- * not extend all the way to the valid file size then restrict this update to
- * the end of the write.
- *
- * This function does not block as blocking on the inode lock in IO completion
- * can lead to IO completion order dependency deadlocks.. If it can't get the
- * inode ilock it will return EAGAIN. Callers must handle this.
- */
-STATIC int
-xfs_setfilesize(
- xfs_ioend_t *ioend)
-{
- xfs_inode_t *ip = XFS_I(ioend->io_inode);
- xfs_fsize_t isize;
-
- if (unlikely(ioend->io_error))
- return 0;
-
- if (!xfs_ilock_nowait(ip, XFS_ILOCK_EXCL))
- return EAGAIN;
-
- isize = xfs_ioend_new_eof(ioend);
- if (isize) {
- ip->i_d.di_size = isize;
- xfs_mark_inode_dirty(ip);
- }
-
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
- return 0;
-}
-
-/*
- * Schedule IO completion handling on the final put of an ioend.
- */
-STATIC void
-xfs_finish_ioend(
- struct xfs_ioend *ioend)
-{
- if (atomic_dec_and_test(&ioend->io_remaining)) {
- if (ioend->io_type == IO_UNWRITTEN)
- queue_work(xfsconvertd_workqueue, &ioend->io_work);
- else
- queue_work(xfsdatad_workqueue, &ioend->io_work);
- }
-}
-
-/*
- * IO write completion.
- */
-STATIC void
-xfs_end_io(
- struct work_struct *work)
-{
- xfs_ioend_t *ioend = container_of(work, xfs_ioend_t, io_work);
- struct xfs_inode *ip = XFS_I(ioend->io_inode);
- int error = 0;
-
- /*
- * For unwritten extents we need to issue transactions to convert a
- * range to normal written extens after the data I/O has finished.
- */
- if (ioend->io_type == IO_UNWRITTEN &&
- likely(!ioend->io_error && !XFS_FORCED_SHUTDOWN(ip->i_mount))) {
-
- error = xfs_iomap_write_unwritten(ip, ioend->io_offset,
- ioend->io_size);
- if (error)
- ioend->io_error = error;
- }
-
- /*
- * We might have to update the on-disk file size after extending
- * writes.
- */
- error = xfs_setfilesize(ioend);
- ASSERT(!error || error == EAGAIN);
-
- /*
- * If we didn't complete processing of the ioend, requeue it to the
- * tail of the workqueue for another attempt later. Otherwise destroy
- * it.
- */
- if (error == EAGAIN) {
- atomic_inc(&ioend->io_remaining);
- xfs_finish_ioend(ioend);
- /* ensure we don't spin on blocked ioends */
- delay(1);
- } else {
- if (ioend->io_iocb)
- aio_complete(ioend->io_iocb, ioend->io_result, 0);
- xfs_destroy_ioend(ioend);
- }
-}
-
-/*
- * Call IO completion handling in caller context on the final put of an ioend.
- */
-STATIC void
-xfs_finish_ioend_sync(
- struct xfs_ioend *ioend)
-{
- if (atomic_dec_and_test(&ioend->io_remaining))
- xfs_end_io(&ioend->io_work);
-}
-
-/*
- * Allocate and initialise an IO completion structure.
- * We need to track unwritten extent write completion here initially.
- * We'll need to extend this for updating the ondisk inode size later
- * (vs. incore size).
- */
-STATIC xfs_ioend_t *
-xfs_alloc_ioend(
- struct inode *inode,
- unsigned int type)
-{
- xfs_ioend_t *ioend;
-
- ioend = mempool_alloc(xfs_ioend_pool, GFP_NOFS);
-
- /*
- * Set the count to 1 initially, which will prevent an I/O
- * completion callback from happening before we have started
- * all the I/O from calling the completion routine too early.
- */
- atomic_set(&ioend->io_remaining, 1);
- ioend->io_error = 0;
- ioend->io_list = NULL;
- ioend->io_type = type;
- ioend->io_inode = inode;
- ioend->io_buffer_head = NULL;
- ioend->io_buffer_tail = NULL;
- atomic_inc(&XFS_I(ioend->io_inode)->i_iocount);
- ioend->io_offset = 0;
- ioend->io_size = 0;
- ioend->io_iocb = NULL;
- ioend->io_result = 0;
-
- INIT_WORK(&ioend->io_work, xfs_end_io);
- return ioend;
-}
-
-STATIC int
-xfs_map_blocks(
- struct inode *inode,
- loff_t offset,
- struct xfs_bmbt_irec *imap,
- int type,
- int nonblocking)
-{
- struct xfs_inode *ip = XFS_I(inode);
- struct xfs_mount *mp = ip->i_mount;
- ssize_t count = 1 << inode->i_blkbits;
- xfs_fileoff_t offset_fsb, end_fsb;
- int error = 0;
- int bmapi_flags = XFS_BMAPI_ENTIRE;
- int nimaps = 1;
-
- if (XFS_FORCED_SHUTDOWN(mp))
- return -XFS_ERROR(EIO);
-
- if (type == IO_UNWRITTEN)
- bmapi_flags |= XFS_BMAPI_IGSTATE;
-
- if (!xfs_ilock_nowait(ip, XFS_ILOCK_SHARED)) {
- if (nonblocking)
- return -XFS_ERROR(EAGAIN);
- xfs_ilock(ip, XFS_ILOCK_SHARED);
- }
-
- ASSERT(ip->i_d.di_format != XFS_DINODE_FMT_BTREE ||
- (ip->i_df.if_flags & XFS_IFEXTENTS));
- ASSERT(offset <= mp->m_maxioffset);
-
- if (offset + count > mp->m_maxioffset)
- count = mp->m_maxioffset - offset;
- end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + count);
- offset_fsb = XFS_B_TO_FSBT(mp, offset);
- error = xfs_bmapi(NULL, ip, offset_fsb, end_fsb - offset_fsb,
- bmapi_flags, NULL, 0, imap, &nimaps, NULL);
- xfs_iunlock(ip, XFS_ILOCK_SHARED);
-
- if (error)
- return -XFS_ERROR(error);
-
- if (type == IO_DELALLOC &&
- (!nimaps || isnullstartblock(imap->br_startblock))) {
- error = xfs_iomap_write_allocate(ip, offset, count, imap);
- if (!error)
- trace_xfs_map_blocks_alloc(ip, offset, count, type, imap);
- return -XFS_ERROR(error);
- }
-
-#ifdef DEBUG
- if (type == IO_UNWRITTEN) {
- ASSERT(nimaps);
- ASSERT(imap->br_startblock != HOLESTARTBLOCK);
- ASSERT(imap->br_startblock != DELAYSTARTBLOCK);
- }
-#endif
- if (nimaps)
- trace_xfs_map_blocks_found(ip, offset, count, type, imap);
- return 0;
-}
-
-STATIC int
-xfs_imap_valid(
- struct inode *inode,
- struct xfs_bmbt_irec *imap,
- xfs_off_t offset)
-{
- offset >>= inode->i_blkbits;
-
- return offset >= imap->br_startoff &&
- offset < imap->br_startoff + imap->br_blockcount;
-}
-
-/*
- * BIO completion handler for buffered IO.
- */
-STATIC void
-xfs_end_bio(
- struct bio *bio,
- int error)
-{
- xfs_ioend_t *ioend = bio->bi_private;
-
- ASSERT(atomic_read(&bio->bi_cnt) >= 1);
- ioend->io_error = test_bit(BIO_UPTODATE, &bio->bi_flags) ? 0 : error;
-
- /* Toss bio and pass work off to an xfsdatad thread */
- bio->bi_private = NULL;
- bio->bi_end_io = NULL;
- bio_put(bio);
-
- xfs_finish_ioend(ioend);
-}
-
-STATIC void
-xfs_submit_ioend_bio(
- struct writeback_control *wbc,
- xfs_ioend_t *ioend,
- struct bio *bio)
-{
- atomic_inc(&ioend->io_remaining);
- bio->bi_private = ioend;
- bio->bi_end_io = xfs_end_bio;
-
- /*
- * If the I/O is beyond EOF we mark the inode dirty immediately
- * but don't update the inode size until I/O completion.
- */
- if (xfs_ioend_new_eof(ioend))
- xfs_mark_inode_dirty(XFS_I(ioend->io_inode));
-
- submit_bio(wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE, bio);
-}
-
-STATIC struct bio *
-xfs_alloc_ioend_bio(
- struct buffer_head *bh)
-{
- int nvecs = bio_get_nr_vecs(bh->b_bdev);
- struct bio *bio = bio_alloc(GFP_NOIO, nvecs);
-
- ASSERT(bio->bi_private == NULL);
- bio->bi_sector = bh->b_blocknr * (bh->b_size >> 9);
- bio->bi_bdev = bh->b_bdev;
- return bio;
-}
-
-STATIC void
-xfs_start_buffer_writeback(
- struct buffer_head *bh)
-{
- ASSERT(buffer_mapped(bh));
- ASSERT(buffer_locked(bh));
- ASSERT(!buffer_delay(bh));
- ASSERT(!buffer_unwritten(bh));
-
- mark_buffer_async_write(bh);
- set_buffer_uptodate(bh);
- clear_buffer_dirty(bh);
-}
-
-STATIC void
-xfs_start_page_writeback(
- struct page *page,
- int clear_dirty,
- int buffers)
-{
- ASSERT(PageLocked(page));
- ASSERT(!PageWriteback(page));
- if (clear_dirty)
- clear_page_dirty_for_io(page);
- set_page_writeback(page);
- unlock_page(page);
- /* If no buffers on the page are to be written, finish it here */
- if (!buffers)
- end_page_writeback(page);
-}
-
-static inline int bio_add_buffer(struct bio *bio, struct buffer_head *bh)
-{
- return bio_add_page(bio, bh->b_page, bh->b_size, bh_offset(bh));
-}
-
-/*
- * Submit all of the bios for all of the ioends we have saved up, covering the
- * initial writepage page and also any probed pages.
- *
- * Because we may have multiple ioends spanning a page, we need to start
- * writeback on all the buffers before we submit them for I/O. If we mark the
- * buffers as we got, then we can end up with a page that only has buffers
- * marked async write and I/O complete on can occur before we mark the other
- * buffers async write.
- *
- * The end result of this is that we trip a bug in end_page_writeback() because
- * we call it twice for the one page as the code in end_buffer_async_write()
- * assumes that all buffers on the page are started at the same time.
- *
- * The fix is two passes across the ioend list - one to start writeback on the
- * buffer_heads, and then submit them for I/O on the second pass.
- */
-STATIC void
-xfs_submit_ioend(
- struct writeback_control *wbc,
- xfs_ioend_t *ioend)
-{
- xfs_ioend_t *head = ioend;
- xfs_ioend_t *next;
- struct buffer_head *bh;
- struct bio *bio;
- sector_t lastblock = 0;
-
- /* Pass 1 - start writeback */
- do {
- next = ioend->io_list;
- for (bh = ioend->io_buffer_head; bh; bh = bh->b_private)
- xfs_start_buffer_writeback(bh);
- } while ((ioend = next) != NULL);
-
- /* Pass 2 - submit I/O */
- ioend = head;
- do {
- next = ioend->io_list;
- bio = NULL;
-
- for (bh = ioend->io_buffer_head; bh; bh = bh->b_private) {
-
- if (!bio) {
- retry:
- bio = xfs_alloc_ioend_bio(bh);
- } else if (bh->b_blocknr != lastblock + 1) {
- xfs_submit_ioend_bio(wbc, ioend, bio);
- goto retry;
- }
-
- if (bio_add_buffer(bio, bh) != bh->b_size) {
- xfs_submit_ioend_bio(wbc, ioend, bio);
- goto retry;
- }
-
- lastblock = bh->b_blocknr;
- }
- if (bio)
- xfs_submit_ioend_bio(wbc, ioend, bio);
- xfs_finish_ioend(ioend);
- } while ((ioend = next) != NULL);
-}
-
-/*
- * Cancel submission of all buffer_heads so far in this endio.
- * Toss the endio too. Only ever called for the initial page
- * in a writepage request, so only ever one page.
- */
-STATIC void
-xfs_cancel_ioend(
- xfs_ioend_t *ioend)
-{
- xfs_ioend_t *next;
- struct buffer_head *bh, *next_bh;
-
- do {
- next = ioend->io_list;
- bh = ioend->io_buffer_head;
- do {
- next_bh = bh->b_private;
- clear_buffer_async_write(bh);
- unlock_buffer(bh);
- } while ((bh = next_bh) != NULL);
-
- xfs_ioend_wake(XFS_I(ioend->io_inode));
- mempool_free(ioend, xfs_ioend_pool);
- } while ((ioend = next) != NULL);
-}
-
-/*
- * Test to see if we've been building up a completion structure for
- * earlier buffers -- if so, we try to append to this ioend if we
- * can, otherwise we finish off any current ioend and start another.
- * Return true if we've finished the given ioend.
- */
-STATIC void
-xfs_add_to_ioend(
- struct inode *inode,
- struct buffer_head *bh,
- xfs_off_t offset,
- unsigned int type,
- xfs_ioend_t **result,
- int need_ioend)
-{
- xfs_ioend_t *ioend = *result;
-
- if (!ioend || need_ioend || type != ioend->io_type) {
- xfs_ioend_t *previous = *result;
-
- ioend = xfs_alloc_ioend(inode, type);
- ioend->io_offset = offset;
- ioend->io_buffer_head = bh;
- ioend->io_buffer_tail = bh;
- if (previous)
- previous->io_list = ioend;
- *result = ioend;
- } else {
- ioend->io_buffer_tail->b_private = bh;
- ioend->io_buffer_tail = bh;
- }
-
- bh->b_private = NULL;
- ioend->io_size += bh->b_size;
-}
-
-STATIC void
-xfs_map_buffer(
- struct inode *inode,
- struct buffer_head *bh,
- struct xfs_bmbt_irec *imap,
- xfs_off_t offset)
-{
- sector_t bn;
- struct xfs_mount *m = XFS_I(inode)->i_mount;
- xfs_off_t iomap_offset = XFS_FSB_TO_B(m, imap->br_startoff);
- xfs_daddr_t iomap_bn = xfs_fsb_to_db(XFS_I(inode), imap->br_startblock);
-
- ASSERT(imap->br_startblock != HOLESTARTBLOCK);
- ASSERT(imap->br_startblock != DELAYSTARTBLOCK);
-
- bn = (iomap_bn >> (inode->i_blkbits - BBSHIFT)) +
- ((offset - iomap_offset) >> inode->i_blkbits);
-
- ASSERT(bn || XFS_IS_REALTIME_INODE(XFS_I(inode)));
-
- bh->b_blocknr = bn;
- set_buffer_mapped(bh);
-}
-
-STATIC void
-xfs_map_at_offset(
- struct inode *inode,
- struct buffer_head *bh,
- struct xfs_bmbt_irec *imap,
- xfs_off_t offset)
-{
- ASSERT(imap->br_startblock != HOLESTARTBLOCK);
- ASSERT(imap->br_startblock != DELAYSTARTBLOCK);
-
- xfs_map_buffer(inode, bh, imap, offset);
- set_buffer_mapped(bh);
- clear_buffer_delay(bh);
- clear_buffer_unwritten(bh);
-}
-
-/*
- * Test if a given page is suitable for writing as part of an unwritten
- * or delayed allocate extent.
- */
-STATIC int
-xfs_is_delayed_page(
- struct page *page,
- unsigned int type)
-{
- if (PageWriteback(page))
- return 0;
-
- if (page->mapping && page_has_buffers(page)) {
- struct buffer_head *bh, *head;
- int acceptable = 0;
-
- bh = head = page_buffers(page);
- do {
- if (buffer_unwritten(bh))
- acceptable = (type == IO_UNWRITTEN);
- else if (buffer_delay(bh))
- acceptable = (type == IO_DELALLOC);
- else if (buffer_dirty(bh) && buffer_mapped(bh))
- acceptable = (type == IO_OVERWRITE);
- else
- break;
- } while ((bh = bh->b_this_page) != head);
-
- if (acceptable)
- return 1;
- }
-
- return 0;
-}
-
-/*
- * Allocate & map buffers for page given the extent map. Write it out.
- * except for the original page of a writepage, this is called on
- * delalloc/unwritten pages only, for the original page it is possible
- * that the page has no mapping at all.
- */
-STATIC int
-xfs_convert_page(
- struct inode *inode,
- struct page *page,
- loff_t tindex,
- struct xfs_bmbt_irec *imap,
- xfs_ioend_t **ioendp,
- struct writeback_control *wbc)
-{
- struct buffer_head *bh, *head;
- xfs_off_t end_offset;
- unsigned long p_offset;
- unsigned int type;
- int len, page_dirty;
- int count = 0, done = 0, uptodate = 1;
- xfs_off_t offset = page_offset(page);
-
- if (page->index != tindex)
- goto fail;
- if (!trylock_page(page))
- goto fail;
- if (PageWriteback(page))
- goto fail_unlock_page;
- if (page->mapping != inode->i_mapping)
- goto fail_unlock_page;
- if (!xfs_is_delayed_page(page, (*ioendp)->io_type))
- goto fail_unlock_page;
-
- /*
- * page_dirty is initially a count of buffers on the page before
- * EOF and is decremented as we move each into a cleanable state.
- *
- * Derivation:
- *
- * End offset is the highest offset that this page should represent.
- * If we are on the last page, (end_offset & (PAGE_CACHE_SIZE - 1))
- * will evaluate non-zero and be less than PAGE_CACHE_SIZE and
- * hence give us the correct page_dirty count. On any other page,
- * it will be zero and in that case we need page_dirty to be the
- * count of buffers on the page.
- */
- end_offset = min_t(unsigned long long,
- (xfs_off_t)(page->index + 1) << PAGE_CACHE_SHIFT,
- i_size_read(inode));
-
- len = 1 << inode->i_blkbits;
- p_offset = min_t(unsigned long, end_offset & (PAGE_CACHE_SIZE - 1),
- PAGE_CACHE_SIZE);
- p_offset = p_offset ? roundup(p_offset, len) : PAGE_CACHE_SIZE;
- page_dirty = p_offset / len;
-
- bh = head = page_buffers(page);
- do {
- if (offset >= end_offset)
- break;
- if (!buffer_uptodate(bh))
- uptodate = 0;
- if (!(PageUptodate(page) || buffer_uptodate(bh))) {
- done = 1;
- continue;
- }
-
- if (buffer_unwritten(bh) || buffer_delay(bh) ||
- buffer_mapped(bh)) {
- if (buffer_unwritten(bh))
- type = IO_UNWRITTEN;
- else if (buffer_delay(bh))
- type = IO_DELALLOC;
- else
- type = IO_OVERWRITE;
-
- if (!xfs_imap_valid(inode, imap, offset)) {
- done = 1;
- continue;
- }
-
- lock_buffer(bh);
- if (type != IO_OVERWRITE)
- xfs_map_at_offset(inode, bh, imap, offset);
- xfs_add_to_ioend(inode, bh, offset, type,
- ioendp, done);
-
- page_dirty--;
- count++;
- } else {
- done = 1;
- }
- } while (offset += len, (bh = bh->b_this_page) != head);
-
- if (uptodate && bh == head)
- SetPageUptodate(page);
-
- if (count) {
- if (--wbc->nr_to_write <= 0 &&
- wbc->sync_mode == WB_SYNC_NONE)
- done = 1;
- }
- xfs_start_page_writeback(page, !page_dirty, count);
-
- return done;
- fail_unlock_page:
- unlock_page(page);
- fail:
- return 1;
-}
-
-/*
- * Convert & write out a cluster of pages in the same extent as defined
- * by mp and following the start page.
- */
-STATIC void
-xfs_cluster_write(
- struct inode *inode,
- pgoff_t tindex,
- struct xfs_bmbt_irec *imap,
- xfs_ioend_t **ioendp,
- struct writeback_control *wbc,
- pgoff_t tlast)
-{
- struct pagevec pvec;
- int done = 0, i;
-
- pagevec_init(&pvec, 0);
- while (!done && tindex <= tlast) {
- unsigned len = min_t(pgoff_t, PAGEVEC_SIZE, tlast - tindex + 1);
-
- if (!pagevec_lookup(&pvec, inode->i_mapping, tindex, len))
- break;
-
- for (i = 0; i < pagevec_count(&pvec); i++) {
- done = xfs_convert_page(inode, pvec.pages[i], tindex++,
- imap, ioendp, wbc);
- if (done)
- break;
- }
-
- pagevec_release(&pvec);
- cond_resched();
- }
-}
-
-STATIC void
-xfs_vm_invalidatepage(
- struct page *page,
- unsigned long offset)
-{
- trace_xfs_invalidatepage(page->mapping->host, page, offset);
- block_invalidatepage(page, offset);
-}
-
-/*
- * If the page has delalloc buffers on it, we need to punch them out before we
- * invalidate the page. If we don't, we leave a stale delalloc mapping on the
- * inode that can trip a BUG() in xfs_get_blocks() later on if a direct IO read
- * is done on that same region - the delalloc extent is returned when none is
- * supposed to be there.
- *
- * We prevent this by truncating away the delalloc regions on the page before
- * invalidating it. Because they are delalloc, we can do this without needing a
- * transaction. Indeed - if we get ENOSPC errors, we have to be able to do this
- * truncation without a transaction as there is no space left for block
- * reservation (typically why we see a ENOSPC in writeback).
- *
- * This is not a performance critical path, so for now just do the punching a
- * buffer head at a time.
- */
-STATIC void
-xfs_aops_discard_page(
- struct page *page)
-{
- struct inode *inode = page->mapping->host;
- struct xfs_inode *ip = XFS_I(inode);
- struct buffer_head *bh, *head;
- loff_t offset = page_offset(page);
-
- if (!xfs_is_delayed_page(page, IO_DELALLOC))
- goto out_invalidate;
-
- if (XFS_FORCED_SHUTDOWN(ip->i_mount))
- goto out_invalidate;
-
- xfs_alert(ip->i_mount,
- "page discard on page %p, inode 0x%llx, offset %llu.",
- page, ip->i_ino, offset);
-
- xfs_ilock(ip, XFS_ILOCK_EXCL);
- bh = head = page_buffers(page);
- do {
- int error;
- xfs_fileoff_t start_fsb;
-
- if (!buffer_delay(bh))
- goto next_buffer;
-
- start_fsb = XFS_B_TO_FSBT(ip->i_mount, offset);
- error = xfs_bmap_punch_delalloc_range(ip, start_fsb, 1);
- if (error) {
- /* something screwed, just bail */
- if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) {
- xfs_alert(ip->i_mount,
- "page discard unable to remove delalloc mapping.");
- }
- break;
- }
-next_buffer:
- offset += 1 << inode->i_blkbits;
-
- } while ((bh = bh->b_this_page) != head);
-
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
-out_invalidate:
- xfs_vm_invalidatepage(page, 0);
- return;
-}
-
-/*
- * Write out a dirty page.
- *
- * For delalloc space on the page we need to allocate space and flush it.
- * For unwritten space on the page we need to start the conversion to
- * regular allocated space.
- * For any other dirty buffer heads on the page we should flush them.
- *
- * If we detect that a transaction would be required to flush the page, we
- * have to check the process flags first, if we are already in a transaction
- * or disk I/O during allocations is off, we need to fail the writepage and
- * redirty the page.
- */
-STATIC int
-xfs_vm_writepage(
- struct page *page,
- struct writeback_control *wbc)
-{
- struct inode *inode = page->mapping->host;
- int delalloc, unwritten;
- struct buffer_head *bh, *head;
- struct xfs_bmbt_irec imap;
- xfs_ioend_t *ioend = NULL, *iohead = NULL;
- loff_t offset;
- unsigned int type;
- __uint64_t end_offset;
- pgoff_t end_index, last_index;
- ssize_t len;
- int err, imap_valid = 0, uptodate = 1;
- int count = 0;
- int nonblocking = 0;
-
- trace_xfs_writepage(inode, page, 0);
-
- ASSERT(page_has_buffers(page));
-
- /*
- * Refuse to write the page out if we are called from reclaim context.
- *
- * This avoids stack overflows when called from deeply used stacks in
- * random callers for direct reclaim or memcg reclaim. We explicitly
- * allow reclaim from kswapd as the stack usage there is relatively low.
- *
- * This should really be done by the core VM, but until that happens
- * filesystems like XFS, btrfs and ext4 have to take care of this
- * by themselves.
- */
- if ((current->flags & (PF_MEMALLOC|PF_KSWAPD)) == PF_MEMALLOC)
- goto redirty;
-
- /*
- * We need a transaction if there are delalloc or unwritten buffers
- * on the page.
- *
- * If we need a transaction and the process flags say we are already
- * in a transaction, or no IO is allowed then mark the page dirty
- * again and leave the page as is.
- */
- xfs_count_page_state(page, &delalloc, &unwritten);
- if ((current->flags & PF_FSTRANS) && (delalloc || unwritten))
- goto redirty;
-
- /* Is this page beyond the end of the file? */
- offset = i_size_read(inode);
- end_index = offset >> PAGE_CACHE_SHIFT;
- last_index = (offset - 1) >> PAGE_CACHE_SHIFT;
- if (page->index >= end_index) {
- if ((page->index >= end_index + 1) ||
- !(i_size_read(inode) & (PAGE_CACHE_SIZE - 1))) {
- unlock_page(page);
- return 0;
- }
- }
-
- end_offset = min_t(unsigned long long,
- (xfs_off_t)(page->index + 1) << PAGE_CACHE_SHIFT,
- offset);
- len = 1 << inode->i_blkbits;
-
- bh = head = page_buffers(page);
- offset = page_offset(page);
- type = IO_OVERWRITE;
-
- if (wbc->sync_mode == WB_SYNC_NONE && wbc->nonblocking)
- nonblocking = 1;
-
- do {
- int new_ioend = 0;
-
- if (offset >= end_offset)
- break;
- if (!buffer_uptodate(bh))
- uptodate = 0;
-
- /*
- * set_page_dirty dirties all buffers in a page, independent
- * of their state. The dirty state however is entirely
- * meaningless for holes (!mapped && uptodate), so skip
- * buffers covering holes here.
- */
- if (!buffer_mapped(bh) && buffer_uptodate(bh)) {
- imap_valid = 0;
- continue;
- }
-
- if (buffer_unwritten(bh)) {
- if (type != IO_UNWRITTEN) {
- type = IO_UNWRITTEN;
- imap_valid = 0;
- }
- } else if (buffer_delay(bh)) {
- if (type != IO_DELALLOC) {
- type = IO_DELALLOC;
- imap_valid = 0;
- }
- } else if (buffer_uptodate(bh)) {
- if (type != IO_OVERWRITE) {
- type = IO_OVERWRITE;
- imap_valid = 0;
- }
- } else {
- if (PageUptodate(page)) {
- ASSERT(buffer_mapped(bh));
- imap_valid = 0;
- }
- continue;
- }
-
- if (imap_valid)
- imap_valid = xfs_imap_valid(inode, &imap, offset);
- if (!imap_valid) {
- /*
- * If we didn't have a valid mapping then we need to
- * put the new mapping into a separate ioend structure.
- * This ensures non-contiguous extents always have
- * separate ioends, which is particularly important
- * for unwritten extent conversion at I/O completion
- * time.
- */
- new_ioend = 1;
- err = xfs_map_blocks(inode, offset, &imap, type,
- nonblocking);
- if (err)
- goto error;
- imap_valid = xfs_imap_valid(inode, &imap, offset);
- }
- if (imap_valid) {
- lock_buffer(bh);
- if (type != IO_OVERWRITE)
- xfs_map_at_offset(inode, bh, &imap, offset);
- xfs_add_to_ioend(inode, bh, offset, type, &ioend,
- new_ioend);
- count++;
- }
-
- if (!iohead)
- iohead = ioend;
-
- } while (offset += len, ((bh = bh->b_this_page) != head));
-
- if (uptodate && bh == head)
- SetPageUptodate(page);
-
- xfs_start_page_writeback(page, 1, count);
-
- if (ioend && imap_valid) {
- xfs_off_t end_index;
-
- end_index = imap.br_startoff + imap.br_blockcount;
-
- /* to bytes */
- end_index <<= inode->i_blkbits;
-
- /* to pages */
- end_index = (end_index - 1) >> PAGE_CACHE_SHIFT;
-
- /* check against file size */
- if (end_index > last_index)
- end_index = last_index;
-
- xfs_cluster_write(inode, page->index + 1, &imap, &ioend,
- wbc, end_index);
- }
-
- if (iohead)
- xfs_submit_ioend(wbc, iohead);
-
- return 0;
-
-error:
- if (iohead)
- xfs_cancel_ioend(iohead);
-
- if (err == -EAGAIN)
- goto redirty;
-
- xfs_aops_discard_page(page);
- ClearPageUptodate(page);
- unlock_page(page);
- return err;
-
-redirty:
- redirty_page_for_writepage(wbc, page);
- unlock_page(page);
- return 0;
-}
-
-STATIC int
-xfs_vm_writepages(
- struct address_space *mapping,
- struct writeback_control *wbc)
-{
- xfs_iflags_clear(XFS_I(mapping->host), XFS_ITRUNCATED);
- return generic_writepages(mapping, wbc);
-}
-
-/*
- * Called to move a page into cleanable state - and from there
- * to be released. The page should already be clean. We always
- * have buffer heads in this call.
- *
- * Returns 1 if the page is ok to release, 0 otherwise.
- */
-STATIC int
-xfs_vm_releasepage(
- struct page *page,
- gfp_t gfp_mask)
-{
- int delalloc, unwritten;
-
- trace_xfs_releasepage(page->mapping->host, page, 0);
-
- xfs_count_page_state(page, &delalloc, &unwritten);
-
- if (WARN_ON(delalloc))
- return 0;
- if (WARN_ON(unwritten))
- return 0;
-
- return try_to_free_buffers(page);
-}
-
-STATIC int
-__xfs_get_blocks(
- struct inode *inode,
- sector_t iblock,
- struct buffer_head *bh_result,
- int create,
- int direct)
-{
- struct xfs_inode *ip = XFS_I(inode);
- struct xfs_mount *mp = ip->i_mount;
- xfs_fileoff_t offset_fsb, end_fsb;
- int error = 0;
- int lockmode = 0;
- struct xfs_bmbt_irec imap;
- int nimaps = 1;
- xfs_off_t offset;
- ssize_t size;
- int new = 0;
-
- if (XFS_FORCED_SHUTDOWN(mp))
- return -XFS_ERROR(EIO);
-
- offset = (xfs_off_t)iblock << inode->i_blkbits;
- ASSERT(bh_result->b_size >= (1 << inode->i_blkbits));
- size = bh_result->b_size;
-
- if (!create && direct && offset >= i_size_read(inode))
- return 0;
-
- if (create) {
- lockmode = XFS_ILOCK_EXCL;
- xfs_ilock(ip, lockmode);
- } else {
- lockmode = xfs_ilock_map_shared(ip);
- }
-
- ASSERT(offset <= mp->m_maxioffset);
- if (offset + size > mp->m_maxioffset)
- size = mp->m_maxioffset - offset;
- end_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)offset + size);
- offset_fsb = XFS_B_TO_FSBT(mp, offset);
-
- error = xfs_bmapi(NULL, ip, offset_fsb, end_fsb - offset_fsb,
- XFS_BMAPI_ENTIRE, NULL, 0, &imap, &nimaps, NULL);
- if (error)
- goto out_unlock;
-
- if (create &&
- (!nimaps ||
- (imap.br_startblock == HOLESTARTBLOCK ||
- imap.br_startblock == DELAYSTARTBLOCK))) {
- if (direct) {
- error = xfs_iomap_write_direct(ip, offset, size,
- &imap, nimaps);
- } else {
- error = xfs_iomap_write_delay(ip, offset, size, &imap);
- }
- if (error)
- goto out_unlock;
-
- trace_xfs_get_blocks_alloc(ip, offset, size, 0, &imap);
- } else if (nimaps) {
- trace_xfs_get_blocks_found(ip, offset, size, 0, &imap);
- } else {
- trace_xfs_get_blocks_notfound(ip, offset, size);
- goto out_unlock;
- }
- xfs_iunlock(ip, lockmode);
-
- if (imap.br_startblock != HOLESTARTBLOCK &&
- imap.br_startblock != DELAYSTARTBLOCK) {
- /*
- * For unwritten extents do not report a disk address on
- * the read case (treat as if we're reading into a hole).
- */
- if (create || !ISUNWRITTEN(&imap))
- xfs_map_buffer(inode, bh_result, &imap, offset);
- if (create && ISUNWRITTEN(&imap)) {
- if (direct)
- bh_result->b_private = inode;
- set_buffer_unwritten(bh_result);
- }
- }
-
- /*
- * If this is a realtime file, data may be on a different device.
- * to that pointed to from the buffer_head b_bdev currently.
- */
- bh_result->b_bdev = xfs_find_bdev_for_inode(inode);
-
- /*
- * If we previously allocated a block out beyond eof and we are now
- * coming back to use it then we will need to flag it as new even if it
- * has a disk address.
- *
- * With sub-block writes into unwritten extents we also need to mark
- * the buffer as new so that the unwritten parts of the buffer gets
- * correctly zeroed.
- */
- if (create &&
- ((!buffer_mapped(bh_result) && !buffer_uptodate(bh_result)) ||
- (offset >= i_size_read(inode)) ||
- (new || ISUNWRITTEN(&imap))))
- set_buffer_new(bh_result);
-
- if (imap.br_startblock == DELAYSTARTBLOCK) {
- BUG_ON(direct);
- if (create) {
- set_buffer_uptodate(bh_result);
- set_buffer_mapped(bh_result);
- set_buffer_delay(bh_result);
- }
- }
-
- /*
- * If this is O_DIRECT or the mpage code calling tell them how large
- * the mapping is, so that we can avoid repeated get_blocks calls.
- */
- if (direct || size > (1 << inode->i_blkbits)) {
- xfs_off_t mapping_size;
-
- mapping_size = imap.br_startoff + imap.br_blockcount - iblock;
- mapping_size <<= inode->i_blkbits;
-
- ASSERT(mapping_size > 0);
- if (mapping_size > size)
- mapping_size = size;
- if (mapping_size > LONG_MAX)
- mapping_size = LONG_MAX;
-
- bh_result->b_size = mapping_size;
- }
-
- return 0;
-
-out_unlock:
- xfs_iunlock(ip, lockmode);
- return -error;
-}
-
-int
-xfs_get_blocks(
- struct inode *inode,
- sector_t iblock,
- struct buffer_head *bh_result,
- int create)
-{
- return __xfs_get_blocks(inode, iblock, bh_result, create, 0);
-}
-
-STATIC int
-xfs_get_blocks_direct(
- struct inode *inode,
- sector_t iblock,
- struct buffer_head *bh_result,
- int create)
-{
- return __xfs_get_blocks(inode, iblock, bh_result, create, 1);
-}
-
-/*
- * Complete a direct I/O write request.
- *
- * If the private argument is non-NULL __xfs_get_blocks signals us that we
- * need to issue a transaction to convert the range from unwritten to written
- * extents. In case this is regular synchronous I/O we just call xfs_end_io
- * to do this and we are done. But in case this was a successful AIO
- * request this handler is called from interrupt context, from which we
- * can't start transactions. In that case offload the I/O completion to
- * the workqueues we also use for buffered I/O completion.
- */
-STATIC void
-xfs_end_io_direct_write(
- struct kiocb *iocb,
- loff_t offset,
- ssize_t size,
- void *private,
- int ret,
- bool is_async)
-{
- struct xfs_ioend *ioend = iocb->private;
-
- /*
- * blockdev_direct_IO can return an error even after the I/O
- * completion handler was called. Thus we need to protect
- * against double-freeing.
- */
- iocb->private = NULL;
-
- ioend->io_offset = offset;
- ioend->io_size = size;
- if (private && size > 0)
- ioend->io_type = IO_UNWRITTEN;
-
- if (is_async) {
- /*
- * If we are converting an unwritten extent we need to delay
- * the AIO completion until after the unwrittent extent
- * conversion has completed, otherwise do it ASAP.
- */
- if (ioend->io_type == IO_UNWRITTEN) {
- ioend->io_iocb = iocb;
- ioend->io_result = ret;
- } else {
- aio_complete(iocb, ret, 0);
- }
- xfs_finish_ioend(ioend);
- } else {
- xfs_finish_ioend_sync(ioend);
- }
-}
-
-STATIC ssize_t
-xfs_vm_direct_IO(
- int rw,
- struct kiocb *iocb,
- const struct iovec *iov,
- loff_t offset,
- unsigned long nr_segs)
-{
- struct inode *inode = iocb->ki_filp->f_mapping->host;
- struct block_device *bdev = xfs_find_bdev_for_inode(inode);
- ssize_t ret;
-
- if (rw & WRITE) {
- iocb->private = xfs_alloc_ioend(inode, IO_DIRECT);
-
- ret = __blockdev_direct_IO(rw, iocb, inode, bdev, iov,
- offset, nr_segs,
- xfs_get_blocks_direct,
- xfs_end_io_direct_write, NULL, 0);
- if (ret != -EIOCBQUEUED && iocb->private)
- xfs_destroy_ioend(iocb->private);
- } else {
- ret = __blockdev_direct_IO(rw, iocb, inode, bdev, iov,
- offset, nr_segs,
- xfs_get_blocks_direct,
- NULL, NULL, 0);
- }
-
- return ret;
-}
-
-STATIC void
-xfs_vm_write_failed(
- struct address_space *mapping,
- loff_t to)
-{
- struct inode *inode = mapping->host;
-
- if (to > inode->i_size) {
- /*
- * punch out the delalloc blocks we have already allocated. We
- * don't call xfs_setattr() to do this as we may be in the
- * middle of a multi-iovec write and so the vfs inode->i_size
- * will not match the xfs ip->i_size and so it will zero too
- * much. Hence we jus truncate the page cache to zero what is
- * necessary and punch the delalloc blocks directly.
- */
- struct xfs_inode *ip = XFS_I(inode);
- xfs_fileoff_t start_fsb;
- xfs_fileoff_t end_fsb;
- int error;
-
- truncate_pagecache(inode, to, inode->i_size);
-
- /*
- * Check if there are any blocks that are outside of i_size
- * that need to be trimmed back.
- */
- start_fsb = XFS_B_TO_FSB(ip->i_mount, inode->i_size) + 1;
- end_fsb = XFS_B_TO_FSB(ip->i_mount, to);
- if (end_fsb <= start_fsb)
- return;
-
- xfs_ilock(ip, XFS_ILOCK_EXCL);
- error = xfs_bmap_punch_delalloc_range(ip, start_fsb,
- end_fsb - start_fsb);
- if (error) {
- /* something screwed, just bail */
- if (!XFS_FORCED_SHUTDOWN(ip->i_mount)) {
- xfs_alert(ip->i_mount,
- "xfs_vm_write_failed: unable to clean up ino %lld",
- ip->i_ino);
- }
- }
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
- }
-}
-
-STATIC int
-xfs_vm_write_begin(
- struct file *file,
- struct address_space *mapping,
- loff_t pos,
- unsigned len,
- unsigned flags,
- struct page **pagep,
- void **fsdata)
-{
- int ret;
-
- ret = block_write_begin(mapping, pos, len, flags | AOP_FLAG_NOFS,
- pagep, xfs_get_blocks);
- if (unlikely(ret))
- xfs_vm_write_failed(mapping, pos + len);
- return ret;
-}
-
-STATIC int
-xfs_vm_write_end(
- struct file *file,
- struct address_space *mapping,
- loff_t pos,
- unsigned len,
- unsigned copied,
- struct page *page,
- void *fsdata)
-{
- int ret;
-
- ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
- if (unlikely(ret < len))
- xfs_vm_write_failed(mapping, pos + len);
- return ret;
-}
-
-STATIC sector_t
-xfs_vm_bmap(
- struct address_space *mapping,
- sector_t block)
-{
- struct inode *inode = (struct inode *)mapping->host;
- struct xfs_inode *ip = XFS_I(inode);
-
- trace_xfs_vm_bmap(XFS_I(inode));
- xfs_ilock(ip, XFS_IOLOCK_SHARED);
- xfs_flush_pages(ip, (xfs_off_t)0, -1, 0, FI_REMAPF);
- xfs_iunlock(ip, XFS_IOLOCK_SHARED);
- return generic_block_bmap(mapping, block, xfs_get_blocks);
-}
-
-STATIC int
-xfs_vm_readpage(
- struct file *unused,
- struct page *page)
-{
- return mpage_readpage(page, xfs_get_blocks);
-}
-
-STATIC int
-xfs_vm_readpages(
- struct file *unused,
- struct address_space *mapping,
- struct list_head *pages,
- unsigned nr_pages)
-{
- return mpage_readpages(mapping, pages, nr_pages, xfs_get_blocks);
-}
-
-const struct address_space_operations xfs_address_space_operations = {
- .readpage = xfs_vm_readpage,
- .readpages = xfs_vm_readpages,
- .writepage = xfs_vm_writepage,
- .writepages = xfs_vm_writepages,
- .releasepage = xfs_vm_releasepage,
- .invalidatepage = xfs_vm_invalidatepage,
- .write_begin = xfs_vm_write_begin,
- .write_end = xfs_vm_write_end,
- .bmap = xfs_vm_bmap,
- .direct_IO = xfs_vm_direct_IO,
- .migratepage = buffer_migrate_page,
- .is_partially_uptodate = block_is_partially_uptodate,
- .error_remove_page = generic_error_remove_page,
-};